Fig. 6.
Sla1-labeled condensates are embedded in a viscoelastic cytosol. (A) Position-sensitive detector (PSD) output signal in volts versus time for acquisitions made at 1 Hz (Top), 2 Hz (Middle), and 5 Hz (Bottom). A bead located in the cytoplasm was oscillated with the acousto-optic deflector in the y-axis of the specimen plane with fixed tweezer movement amplitude (normalized blue curve) at different frequencies. The recorded PSD raw traces (black points) were normalized to a corresponding magnitude range (coherence cutoff of 0.9). (B, Inset) Power spectrum of the oscillated bead (black) with magnitude of response as a function of frequency. (C) Decomposition of G* as a function of frequency into G′ (storage modulus; darker squares) and G″ (loss modulus; light shade circles) for beads distributed at both the cell periphery and interior (see schematic Inset; mean ± SD; n = 17 cells) with an average trap stiffness ktrap (mean ± SE; 8.0 × 10−5 ± 2.7 × 10−5 N⋅m−1) and photodiode sensitivity factor β (mean ± SE; 10.7 × 103 ± 2.3 × 103 nm⋅V−1).